In conventional technology, coal is used to produce coal gas, natural gas, or used to produce gas by coking at high temperature, medium temperature or low temperature. However, the said technology is required to form pulverized coal into blocks or sift lump coal, which increases the cost of raw material, or results in the produced gas without a high heat value, a big additional value and significant economic and social benefits. The heating mode of furnace can be classified as external-heating mode, internal-heating mode and hybrid-heating mode. The heating medium in external-heating furnace is not contact directly with raw materials and heat is transferred from furnace wall. The heating medium in the internal-heating furnace contacts with the raw materials directly, and the heating methods are classified as solid heat carrier mode and gas heat carrier mode according to different heat media.
At present, there are two kinds of conventional coal decomposition apparatuses, one of which has an up-draft kiln structure. The up-draft kiln structure is used for combusting flue gas and combustible gases produced by coal, which has low gas purity and a low additional value, as well as partially discharge of gas, which results in a significant resources wasting and environmental pollution. Another kind of coal decomposition apparatus has a shaft kiln structure. In the structure, coal lumps are placed on clapboard with holes, and a heater is provided above the coal lumps. Because the coal lumps on the clapboard are accumulated to a certain thickness, so they cannot be uniformly heated and decomposed, and are required to be cyclically heated and decomposed by the decomposed gas. More importantly, since the presence of large amount of holes for ventilation and circulatory function provided on the clapboard, pulverized coal can leak through the holes. To avoid this, it is necessary to process the pulverized coal into coal briquette when introducing it into the shaft kiln. Thus, it will increase the cost of pulverized coal decomposition, and reduce the economic benefits because the pulverized coal cannot be directly used for coal decomposition in up-draft kiln.
Furthermore, in order to change the said problems, the patent (authorized notice No.: CN 101985562B) named as the horizontal separation equipment with crushed coal, pulverized coal multiple burners discloses a kind of horizontal separation equipment with crushed coal, pulverized coal multiple burners comprising of a transverse rotary kiln, and the said rotary kiln includes a feed inlet and a feed outlet, and multiple closely-spaced burners are set inside the said rotary kiln body in the direction of the kiln; multiple closely-spaced gas intake pipes and their parallel multiple closely-spaced air intake pipes are set correspondingly along one side of the said closely-spaced burners, the said gas intake pipe connected to its corresponding burner, the said closely-spaced air intake pipe connected to its corresponding burner, and multiple closely-spaced radiating pipes are set correspondingly along another side of the said closely-spaced burners, the said multiple closely-spaced burners connected to their corresponding closely-spaced radiating pipes; the said multiple closely-spaced burners are provided with theirs corresponding multiple burners; the said multiple closely-spaced burners, radiating pipes, gas intake pipes, air intake pipes and the inner wall of rotary kiln form the passage to push and separate crushed coal and pulverized coal. The said embodiment is a good solution for the technical problem of adequate heating and rapid decomposition of pulverized coal, but the problem is that a small number of heating pipes fails to meeting the requirement of rapid and large heat conduction, the heating pipes inside the kiln are therefore dense, and the over crowded pipes cause inconvenience for personnel when performing the overhaul and maintenance, in addition, during its operation, it requires for real-time monitoring of temperature and operation of various segments of each pipe, and collection and analysis of a great number of data. When any segment of a certain pipe is in abnormal state, analysis on it shall be made or shut down for maintenance, which fails to meet the continuous and reliable manufacturing and operation and will cause significant economic loss for large-scaled high temperature integrated equipment under continuous operation.
Furthermore, JP2003277761 A 20031002 document discloses the patent with a title of CATALYTIC HEATING CARBONIZATION FURNACE, which intends to solve the problem: “To provide a catalytic heating carbonization furnace that reduces a running cost of the furnace for carbonization treatment of organic wastes”. But in this technical embodiment, the catalytic carbonization furnace is provided as a drying part used for the substance carbonization, playing a role of carbonization, and thermal decomposition part used for the carbonization of substances to be processed; firstly, the carbonization furnace uses the hot gas generated from the heating catalytic combustion for the decomposition of organic matters, after which, further decomposition is conducted by using the exhaust heat, and the temperature of organic waste drops as a result of the drying by the heat accumulator to improve the heat energy utilization efficiency. However, such catalytic burning equipment makes it hard for the processing of coal material, and fails to meet the demand for rapid decomposition of pulverized coal and crushed coal, and there are also problems with its security and reliability.